nice work... rele nice work on the poses and figure structure, but I dunno... your style of heads has a rounded jaw which im not used to lol, i'm used to straight lined jaws and stuff... but it's ur style so great work! keep it up!

Here are some more sketches. I used some references to try grasp the concept better, but I don't think I got very far in doing so. Crits and comments are welcome. I'll leave it at that for now.
Thank you.

Mercenary, you seem to have some serious skills, but weaknesses in several areas. If you concentrate on smoothing those out, you'll soon kick serious butt.
Pay attention to the lower faces. Your jaws don't look natural and often your faces' chins are way too small and weak. Study some photos or people in real life, the jaw and the chin are more pronounced than you might think, especially in males, but also in females.
Concentrate on the eyes, too. You tend to place them too close together and/or draw them too large. Often, when you're drawing at a small scale and the pencil's not fine enough to catch all the details, it helps to just define the eyes with a few choice lines and leave out the finer details. This works much better most of the time.
Well, I hope this will help. Have fun drawing!

Mercenary, you seem to have some serious skills, but weaknesses in several areas. If you concentrate on smoothing those out, you'll soon kick serious butt.
Pay attention to the lower faces. Your jaws don't look natural and often your faces' chins are way too small and weak. Study some photos or people in real life, the jaw and the chin are more pronounced than you might think, especially in males, but also in females.
Concentrate on the eyes, too. You tend to place them too close together and/or draw them too large. Often, when you're drawing at a small scale and the pencil's not fine enough to catch all the details, it helps to just define the eyes with a few choice lines and leave out the finer details. This works much better most of the time.
Well, I hope this will help. Have fun drawing!

Here's another for the slaughter. This one is concept art. Two characters below are not completely finished nor did they turn out the way I had previously sketched out. But here's some background information on the two. The girl, sorry woman, is a scientist (doesn't really look like it) or something like that; she gets accidently cloned and the guy next to her is the result. Explanation, glitch in the system. The story doesn't revolve around the incident but I thought it would be interesting to have a character introduced that way.

Hopefully I can get some suggestions or criticism to improve it.
Pleasure.

Here's another sketch, with the use of some references. I'll try to post more concentrated sketches as time progresses. But to keep this sketchbook from being devoured by the masses, the incomplete will make themselves known.

Here's some more sketches, I tried to apply some of the suggestions you made. But to try is to fail, so I'll have to work harder next time. But to keep you posted and keep this thread active I decided to share some recent work with you.
Pleasure.